A newly developed covid-19 home self-test kit, where you poke yourself in the nose and do the analysis at home, is considered to be as reliable as antigen testing performed by healthcare professionals

Doctors at Aarhus University Hospital have developed a home-self-test kit, where citizens can take the sample in the outer part of the nose and read the result themselves. It provides e.g. opportunity to do it at home. The reliability of the home self-test is assessed to be in line with approved quick tests performed by health professionals. Thus, the test could be an important new contribution to a safe reopening of Denmark.

At the end of 2020, Aarhus University Hospital experienced a large spread of infection among the employees at the Covid ward. It was unclear how the staff became infected and it was difficult to slow the spread of the infection. Therefore, the staff of the department were systematically offered a quick test when they showed up for work. The staff grafted each other because the antigen test is only approved for professional use.

“We asked ourselves if it would not be better if the staff could test themselves before going to work, so they could avoid risking infecting others in public transport and on arrival at the workplace, says chief physician Lars Østergaard, who has previously researched i.a. home test for chlamydia”.

But quick tests today must not be performed by citizens themselves, because the current quick tests are not approved for this in Denmark.

Therefore, we developed a home self-test kit with a quick test, written information and an instructional video and started to find out how well the home self-test works compared to PCR tests performed by health professionals.

The quick test is an antigen test that takes place by inoculating oneself 2 cm up in the nose with a cotton swab. Then place the cotton swab in a container with liquid, which is poured onto a plate. If the plate shows one line, the test is negative. If there are two lines, the test is positive.

The project included 375 randomly selected individuals who, after a PCR test, received a home self-test kit. The sensitivity was found to be above 60%, which is equivalent to the reliability that has been demonstrated in scientific studies of quick tests performed by health professionals. The specificity was 100%, and this means that a positive answer is just as safe as with a PCR test, and with a positive answer you can therefore immediately start infection detection and isolation without waiting for a confirmatory PCR test.

The home self-test cannot replace a PCR test and therefore it cannot be used to ask than diagnosis. But it can help prevent the spread of infection, because you get an answer immediately, and you can take the test before you go out to your home. Therefore, the home self-test may be an important supplement to the test strategy to ensure a successful reopening of society, says Lars Østergaard.

The new test can also be an important tool in following the spread of infection in Denmark, because a representative sample of the population can take the test at home, for example. twice weekly. This could contribute to a more accurate picture of the spread of infection and thus provide a better basis for an ongoing assessment of the reopening.

According to the rules, the doctors have reported the home-self test as a creation of a new product with the possibility that interested external companies can use the results for an approval and subsequent marketing.

Facts about the quality development project

• In the spring of 2021, the doctors offered citizens who were PCR tested for coronavirus in Testcenter Aarhus, a home test kit consisting of a quick test, written information on how the test is performed.
• In a subsequent period, the doctors encouraged all citizens who tested positive with PCR tests in Testcenter Aarhus to contact the doctors and have a home test kit brought home.
• The PCR test is a very sensitive test method that looks for genetic material from coronavirus. Antigen test is a less sensitive and accurate test method that detects viral proteins (antigens) in the sample.
• 375 citizens participated in the project. The sensitivity of the home test was over 60% and the specificity was 100%. (The sensitivity is an expression of how large a proportion of patients are correctly diagnosed with covid-19. The specificity is an expression of how large a proportion of healthy people are correctly classified with the test.)
• Two out of three participants preferred the home test. Typically because it was comfortable to perform, did not require transportation to a test center and the short response time.
• In a similar project with tests from another company, about 450 citizens were included and the results were roughly the same.
• The results have not yet undergone peer review and are thus not yet published in a scientific journal.

The National Board of Health recommends the use of antigen tests for:

• Staff at care centers, etc.
• Schools and other educational institutions
• Workplaces
• Contacts identified through the Infectious Disease app
• ‘Other contacts’ who have been in close proximity to the infection without being ‘close contact’)
• Selected groups with high incidence of covid-19
• Cultural and sporting events
• Reopening of a large number of areas in the health and municipal area
• Together with PCR test using fast response in connection with. hospitalization, discharge or transfer of patient

Recommendations for the use of antigen testing, version 2.1, National Board of Health 14 April 2021.

More details: HERE (Danish)

Source: rm.dk, tv2, dr